The incident occurred at around 12:10 P.M. yesterday near Kibbutz Misgav Am. A military engineering force with the support of an infantry unit operated in a buffer zone between the international border, also known as the Blue Line, delineated by the United Nations following the IDF withdrawal from southern Lebanon in 2000.

The Israeli troops were trimming tree branches blocking the view from IDF surveillance positions. Harari commanded activities on the Israeli side of the fence, at a distance from a crane that was busy trimming the trees.

According to GOC Northern Command Gadi Eizenkot, the arm of the crane crossed over the fence by about half a meter. In response, Lebanese snipers shot and killed Harari and seriously injured the company commander, Capt. Ezra Lakia, from Kfar Harif.

Harari is the first casualty on the northern border since late August 2006, and the second to have died there since the end of the war. Lt. Col. Emanuel Moreno was killed a week after the Second Lebanon War ended.

The IDF responded to the shooting yesterday and the Lebanese forces to fled the scene. About 30 minutes later, rocket-propelled grenades were fired at an IDF tank near the border. The IDF responded with artillery and helicopter gun ships targeting the regional headquarters and local positions of the Lebanese Army.

Reports coming out of Lebanon indicate four were killed in the incident - three soldiers and one journalist. The Lebanese Army and Hezbollah were careful not to fire any rockets or mortars into Israel.

Lebanon said Israel was to blame for provoking its forces, however senior IDF officers insisted last night that the IDF had not in any way violated Lebanese sovereignty.

The fact that it was Lebanese Army troops and not Hezbollah fighters who shot and killed an IDF battalion commander yesterday is the primary reason behind Israel's relatively measured response to the provocation. Had Hezbollah claimed responsibility for Harari's killing, it is fair to assume the IDF would have responded along the entire southern Lebanese front.

The Lebanese Army'sinvolvement immediately led to a significant diplomatic response, including on the part of the U.S. administration which, along with the United Nations, led an international effort to contain the situation.

The specific spot where yesterday's exchange of fire occurred is one of dozens of similar enclaves along the border, which range in width from several dozen meters to a little more than a kilometer.

Since 2006, having learned its lesson from the Second Lebanon War, the IDF has made a point of showing its presence in these enclaves. The incident which sparked that war - when a Hezbollah force ambushed an IDF patrol and kidnapped two reservists - occurred from within such an enclave.

All IDF operations carried out in these enclaves are coordinated with UNIFIL, as was the trimming of the trees yesterday. It is the job of the UN peacekeepers, in turn, to inform the Lebanese Army.

In recent months, however, Lebanese troops have behaved aggressively, especially near the enclaves. On a number of occasions, Lebanese soldiers were seen aiming their rifles and anti-tank rockets at the Israeli forces. Moreover, cooperation with UNIFIL has deteriorated on the Lebanese side.

Israeli security sources say Hezbollah is stirring the winds of war among senior Lebanese Army figures, many of whom were recently heard praising the "resistance."

Northern Command attributes the escalation to the new commander of the Lebanese Army's Brigade 9, whose soldiers were involved in the incident yesterday. A Shi'ite officer with links to Hezbollah is now heading the unit, a somewhat ironic turn of events as the deployment of the Lebanese Army along the border was in part aimed at removing Hezbollah from the region.

At the IDF, the assumption is that the incident was initiated by local Lebanese Army officers with ranks between company commander to brigade commander, without the direct involvement of Hezbollah. The Lebanese soldiers are said to have taken up positions in advance, probably because they'd been instructed to "show their presence" vis-a-vis the IDF.

While it's possible they had been given advanced orders to open fire, an officer on the ground could have perhaps interpreted the spirit of the orders he received in that way. In any event, it appears the incident was more of an ambush than a momentary conflagration. If this is the case, it raises the perennial intelligence question: How was the IDF unaware of it when even Lebanese media in the area were informed and present?

The Northern Command is now considering modifying the orders to the troops on movement along the border, but no changes have been made to the orders on engaging the enemy.

Prime Minister Benjamin Netanyahu said last night that Israel considers the shooting a grave violation of UN Security Council Resolution 1701, passed after the Second Lebanon War.

Neither Lebanon nor Israel are interested in war at this time, certainly not with Israel's north being filled with tourists - hence the measured IDF response. Senior IDF officers were not necessarily pleased about this, advocating a much more heavy-handed reaction.

The main problem is that there is another actor involved in the equation - Hezbollah - which has been under intense pressure over the past few weeks thanks to expectations that senior figures in the Shi'ite group would be charged with the assassination of former Lebanese prime minister Rafik Hariri.

While Hezbollah might make do with yesterday's exchange of fire, in which it suffered no damage, it's hard to avoid the sense that the group's secretary general, Hassan Nasrallah, is most likely pleased with the development.

Meanwhile, although it is not yet possible to draw a clear link between the rocket attacks on Eilat and Ashkelon over the weekend and yesterday's incident in the north, tension in the region is on the rise. There have been reports in Lebanon about a new Gaza-bound aid flotilla scheduled to depart this coming weekend after it had been held up for the past two months, and there will likely be extra effort on the part of the Americans to ensure that the situation does not escalate further.

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